Chip Somodevilla/Getty Images(WASHINGTON) -- U.S. Park Police clad in riot gear and on horseback raided the Occupy DC camp on Saturday to enforce a ban on camping in McPherson Square, a federal park, authorities said.

“They effectively removed any kind of bedding from the tents and they’re going to start searching them soon,” Legba Carrefour, a spokesperson for Occupy DC told ABCNews.com. “We’re still watching this unfold. The cops are still here in force.”

Four people were arrested after stepping inside police barricades that surrounded a statue of General McPherson, Carrefour said.

Last week, U.S. Park Police announced it would enforce a ban on camping in the park.

Regulations in the federal park permit protesters to stay around the clock and have tents on the premises, however they are barred from sleeping.

A handful of Occupy DC protesters have gone on a no-sleep strike to protest the rule.

“People are focusing on saving their personal possessions. The plan is to regroup and then we are going to escalate,” Carrefour said. “Occupying isn’t limited to parks and squares.”

The D.C. encampment is one of the few camps still standing after the Occupy Wall Street movement began in New York City’s Zuccotti Park on Sept. 17.